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81.
The hematologic disorder beta-thalassemia major is relatively common in Southern Italy. Stroke is a well described, though infrequently reported, complication of this disorder. We now report our experience regarding 300 children with beta-thalassemia major examined at the University of Catania, Italy, over a 20-year period. We encountered 9 patients (3%; 3 males, 6 females) with beta-thalassemia major who had hemorrhagic stroke. Two groups of patients can be identified: group 1 (2 patients 22%) with early-onset post-transfusion hemorrhage and group 2 (7 patients 77%) with delayed post-transfusion hemorrhage. In the first group, the hemorrhage occurred within 48 hours following blood transfusion. In the second group, hemorrhage occurred 7-15 days from last transfusion. In 5 patients out of 7 of this second group the first transfusion and ictal event both occurred after age five, suggesting prolonged chronic anemia might play a role in the hemorrhage.  相似文献   
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BACKGROUND AND AIMS: Skinfold anthropometry has been used to evaluate the nutritional status in cirrhosis. Such estimates are based on the calculations which derive from healthy subjects and may not apply to cirrhotic patients. We aimed to calculate the limits of agreement between Skinfold anthropometry (SA) and dual-energy X-ray absorptiometry (DXA) in estimating body fat in cirrhotics. METHODS: Forty cirrhotic patients were studied by both methods. The limits of agreement were estimated by the Bland and Altman method. RESULTS: Percentage body fat was similar when measured by DXA and SA (29.6 +/- 9.2 vs 28.9 +/- 7.5 %). Body fat mass was also similar (20.3 +/- 8.4 vs 20.3 +/- 7.7 kg). The limits of agreement between DXA and SA measurements were -7.04 (95%CI: -9.55 to -5.2) +8.56 (95%CI: +10.7 to +6.4.) in the assessment of percentage body fat and -5.32 (95%CI: -6.77 to -3.87) +5.24 (95%CI: +3.79 to +6.69) in the assessment of fat mass. CONCLUSION: Percentage body fat can be evaluated by SA or DXA with a difference of less then 5% in the majority of cirrhotic patients without overt fluid retention. This result is important when considering the large applicability of SA.  相似文献   
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Protein kinase C (PKC) comprises a family of ubiquitous enzymes transducing signals by the lipophilic second messenger sn-1, 2-diacylglycerol (DAG). Teleocidin and its structurally simpler congener indolactam-V (ILV) bind to PKC with high affinity. In this paper, we report our computational docking studies on ILV binding to PKC using an automatic docking computer program, MCDOCK. In addition, we used site-directed mutagenesis to assess the quantitative contribution of crucial residues around the binding site of PKC to the binding affinity of ILV to PKC. On the basis of the docking studies, ILV binds to PKC in its cis-twist conformation and forms a number of optimal hydrogen bond interactions. In addition, the hydrophobic groups in ILV form "specific" hydrophobic interactions with side chains of a number of conserved hydrophobic residues in PKC. The predicted binding mode for ILV is entirely consistent with known structure-activity relationships and with our mutational analysis. Our mutational analysis establishes the quantitative contributions of a number of conserved residues to the binding of PKC to ILV. Taken together, our computational docking simulations and analysis by site-directed mutagenesis provide a clear understanding of the interaction between ILV and PKC and the structural basis for design of novel, high-affinity, and isozyme-selective PKC ligands.  相似文献   
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INTRODUCTION: Limited information exists concerning physician staffing at mass gathering events. METHODS: A retrospective review of the preparation, planning, and provision of medical care for the United States Air Show was performed. Patient encounters from the air show for the years 1981-1991 also were evaluated. RESULTS: The frequency rate of overall encounters was 8.45 patients/10,000 spectators and hospital transport rate was 0.6/10,000 spectators. The majority of complaints were related to heat or minor injuries. During this period, emergency physicians played a vital role in both medical planning and on-site staffing. Emergency medicine residents also participated. A small patient population received direct benefit from on-site physician intervention. CONCLUSION: The on-site emergency physician is of benefit in event preplanning and reducing the burden on the EMS system during mass gathering events.  相似文献   
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Out of 142 consecutive cases of fracture of the tibial plateau 48 cases (34%) of complex fractures are taken into consideration. Surgical treatment is based on two types of osteosynthesis: 1) osteosynthesis "of election" with interfragmentary plates and screws, which was used in most of the cases; 2) minimal osteosynthesis with Barr or lag screws, when there are lesions of the soft tissue and capsuloligamentous lesions. A total of 69% of the results were satisfactory (good and excellent). The most unfavorable prognostic factors are comminution of the fracture and residual widening of the tibial plateau.  相似文献   
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Abstract: Spectroscopic techniques have been used to study the conformations of several synthetic peptides with sequences corresponding to the repeat regions of the circumsporozoite proteins of Plasmodium vivax, variants vk‐210 and vk‐247. As has previously been shown for P. falciparum, turn‐like folded conformations are observed, in rapid dynamic equilibrium with extended‐chain forms. These results are consistent with the known similarity of the structural, biosynthetic and immunological properties of the circumsporozoite proteins of different plasmodial species. Additionally, the observation of folded conformers provides a rationale for the effectiveness of these peptides as immunogens and potential vaccines.  相似文献   
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